Searching For Exotic Beetles - Harvard University

Searching for Exotic BeetlesNichole K. CampbellWintentional introductions (primarily plants)have turned out to be invasive pests. Not allintroduced species become agricultural or forest pests; typically, one in seven exotic speciesis considered invasive. There is often a lapsebetween the time the pest is introduced andthe time that the pest is discovered or reportedin the United States; unfortunately this oftenallows new pest populations to build.Beetle PatrolIn 2009, PPQ is conducting exotic beetle trapping around the Boston port area as part of theUSDA’s national wood borer and bark beetlesurvey. The Boston port area may be a high-riskPeter Del Tredicihen non-native species of plants,animals, and disease organisms areintroduced to other regions they havethe potential to become serious pest problems in their new location. Concern over theintroduction of potentially damaging specieshas led the Plant Protection and Quarantine(PPQ) program—part of the USDA Animal andPlant Health Inspection Service—to increase itsdomestic surveillance for non-native species inthe United States over the past several years.Most exotic (non-native) species enter theUnited States through international movement of people, commodities, and conveyances.Most are accidental introductions, though someA cargo ship heads toward the port of Boston, passing between Spectacle Island and Deer Island in Boston Harbor.

area for the introduction of new exotic forestpests because of the high volume of cargo importsthat enter the United States through it.Commodities entering the port are oftenshipped in solid wood packing material, apotential harbor for insect pests of trees. Priorto 2005, there were no regulations requiringthe treatment of solid wood packing materialfor the prevention of pest introductions. Today,all foreign solid wood packing material must befumigated or heat treated to prevent new forestpests from entering the United States throughthat very high-risk pathway.The goals of the USDA’s national wood borerand bark beetle survey are to obtain information about: The presence, distribution, orabsence of target species. The advent of new species. Patterns of distribution throughout the United States and possiblepathways for introduction. The phenology of target exoticspecies in the United States andtheir selection of hosts. The characteristics of high-riskhabitats or sites. The survey methods themselves.When selecting survey sites, we primarilytarget cargo transport companies, businessesthat receive imports, and areas around the portof entry where there are host trees that couldsupport the establishment of exotic beetles.PPQ has chosen twenty locations within15 miles of the port of Boston for the woodborer and bark beetle survey. One of the siteschosen this year is the Arnold Arboretumbecause of its close proximity to the Bostonport and the presence of a wide variety of treespecies in its collections.Setting the TrapThe survey involves trapping and identifyingbeetles in order to determine if exotic speciesare present in the area. We placed three Lindgren12-funnel traps at each of the twenty selectedlocations for a total of sixty traps in the Bostonarea. Each trap is baited with one, or a combina-Nichole K. Campbell32 Arnoldia 67/1One of the Lindgren funnel traps at the Arnold Arboretum.tion, of the following lures: ultra high releaseethanol, ultra high release alpha-pinene, or the3-ips lure. The volatiles in the lures simulatestressed or dying hardwood and softwood trees,the types of host trees that many of the exoticbeetles are attracted to.The traps are hung in trees, on poles, or onfences near target hosts. Traps are placed a minimum of 25 meters (82 feet) apart to preventvolatiles from mixing in the air and deterringbeetles. Each trap has a collection cup at thebottom that is filled with non-toxic antifreezeto preserve the collected beetles. The trappingperiod will last from mid March through theend of August to cover a range of emergenceperiods of the target beetles. Bark and ambrosiabeetles typically emerge in early to late spring,while larger wood-boring beetles typicallyemerge later in summer through fall. The trapsare serviced on a bi-weekly schedule to collectany trap contents and replace lures as needed.All of the trapped beetles will be sent to theCarnegie Museum of Natural History, Sectionof Invertebrate Zoology, in Pittsburgh, Pennsylvania. They will be screened by qualifiedexperts to determine if they are the target exoticbeetles or other non-native beetles.Determining the potential invasiveness ofthese exotic beetles is difficult since there isvery little research information available formost of them. Often, they are not studied intheir native countries if they do not cause eco-

Exotic Beetles 33nomic damage there. We can’t predict exactlyhow an introduced beetle species will affectforests in the United States, but experts do tryto make educated guesses.If any exotic beetles are found they will beconfirmed by PPQ experts, and state and localauthorities will be notified. The USDA’s NewPest Advisory Group (part of PPQ), in conjunction with state and local officials, wouldthen evaluate the new pest risk and determinethe appropriate action to take to protect ournational forests and agricultural industries.A Gallery of BeetlesHylurgus ligniperda(Red-haired Pine Bark Beetle)Native: Europe, Mediterraneanareas, Africa, and parts of AsiaEntered U.S.: Introduced nearRochester, New York, in 1994. Foundin a Lindgren funnel trap. Has beenfound in four counties.Host: Pinus spp. (pines) preferred.Also, Abies spp. (firs); Larix spp.(larches); Picea spp. (spruces);Pseudotsuga spp. (Douglas-firs)Damage: Affects bark, stem,root, trunk, and seedlings. Feed anddevelop in tunnels beneath the bark.They are know vectors of the rootdisease fungi Leptographium spp.and Ceratocystis spp.Milan Zubrik, Forest ResearchInstitute – Slovakia, Bugwood.orgIps sexdentatus (Six-toothed Bark Beetle)Six-toothed bark beetles in galleries.William M. Ciesla, Forest Health ManagementInternational, Bugwood.orgHere are some of the exotic beetles targeted in the survey:Red-haired (or goldenhaired) pine barkbeetles under the barkof a Monterey pine(Pinus radiata).Native: Mainland Asia and EuropeEntered U.S.: Has been intercepted atports of entry. Has not been found domestically beyond ports.Host: Pinus spp. (pines) preferred. Also,Abies spp. (firs); Larix spp. (larches); Piceaspp. (spruces); Pseudotsuga spp. (Douglas-firs)Damage: Affects inner bark, leaf, stem,and whole plant. Mates, develops, and feedsin tunnels beneath the bark. Mainly attacksstressed or dying trees. It can kill trees ofcommercial importance. It also introducesblue stain fungi (Ophiostoma spp.) intohost trees which hasten the death of tree,discolor wood, and can result in loss oflumber grade and value.

34 Arnoldia 67/1David Cappaert, Michigan State University, Bugwood.orgnfortunately, many exotic wood-boring beetles are not attracted to trapsbaited with volatiles and can only be surveyed for visually. This requirestrained spotters using binoculars from ground level, or professionaltree climbers knowledgeable in insect signs and symptoms. The Asian longhorned beetle (ALB) (Anoplophora glabripennis) is a highly destructive invasivebeetle that can only be surveyedfor in this manner. There is ongoing research to identify moreeffective survey methods for thisdevastating pest.Larvae of the Asian longhornedbeetle tunnel into the heartwoodof live healthy trees, eventuallykilling their hosts. Favored species are maples, birches, Ohiobuckeye, elms, horse chestnut,and willows. ALB, and efforts toeradicate it, have resulted in theloss of thousands of street trees inseveral states. ALB was detectedin Worcester, Massachusetts, inAugust, 2008, and its potentialspread is of great concern in New England. Volunteers will be educated to surveyfor ALB throughout Massachusetts this year. Visual surveys and education outreach for ALB will be conducted in all New England states during 2009. For moreinformation about ALB, please visit: http://www.aphis.usda.gov/oa/alb/alb.htmlor http://massnrc.org/pests/alb/Emerald ash borer (EAB) (Agrilus planipennis) is another highly destructivebeetle that has spread in regions of the United States and Canada. EAB attacksash trees (Fraxinus spp.) and has been moved from its introduction point inMichigan to other states primarily through movement of nursery stock andfirewood. We have not detected EAB in Massachusetts yet, but a survey for itis planned for this year. TheMassachusetts Department ofConservation and Recreation,Division of Forestry, willplace purple panel sticky trapsbaited with lures at twentyhigh-risk locations such ascampgrounds, nurseries, andwood processors. Currently,there are no plans to trap insidethe Arnold Arboretum for EABbecause it is not a high-risklocation for the introductionof this pest. For more information about EAB, please visit:www.emeraldashborer.infoKenneth R. Law, USDA APHIS PPQ, Bugwood.orgUTwo Highly Destructive Exotic Beetles

Ips typographus(European Spruce Bark Beetle)Native: Europe and AsiaEntered U.S.: Has been intercepted in trapsin Indiana (1995) and Maryland (2002). It is notknown to be established in the U.S.Host: Picea spp. (spruces) preferred. Also,Abies spp. (firs); Larix spp. (larches); Pinus spp.(pines); Pseudotsuga spp. (Douglas-firs)Damage: Affects bark, crown, foliage, leaf,stem, and whole plant. Considered one ofthe most serious pests of spruce in Europe.It vectors a blue stain fungus (Ceratocystispolonica) which can also kill the host. It causesmajor economic losses when it is in outbreaknumbers and can cause severe decline inspruce populations within its native range.Males aggregate and colonize a stressed treeby boring into the bark and preparing nuptialchambers. The females are then attracted tothe chambers to mate. The females lay eggsin maternal galleries where the larva willdevelop. They can have multiple generationsin a year depending on temperature.Dead spruce trees in Slovakia,killed by European spruce bark beetles.Xyleborus seriatus (No common name; very little is known about this beetle.)Native: China, Russia, Japan, Korea, TaiwanEntered U.S.: Intercepted in Lindgren trap in Massachusetts in 2005, the first NorthAmerican record. This beetle was also trapped in Maine in 2008.Host: Acer spp. (maples), Aesculus spp. (buckeyes), Alnus spp. (alders), Betula spp. (birches),Cryptomeria spp., Fagus spp. (beeches), Larix spp. (larches), Pinus spp. (pines), Prunus spp. (cherries),Quercus spp. (oaks), Thuja spp. (arborvitae), Tsuga spp. (hemlocks), etc. Large possible host range.Damage: Very little data. Is known to be associated with Ambrosiella fungi. Spores of asymbiotic fungi are carried on their bodies to new galleries. Larvae and adults feed on thisfungi growing between the bark and sapwood. Thought to be a secondary pest and will not killhealthy trees. Several Xyloborus species are potential survey targets.Xylotrechus hircus (No common name; very little is known about this beetle.)Native: Native to Eastern Russia, China, KoreaEntered U.S.: Intercepted in Lindgren trap in Oregon in 1999; not known to be established.Host: Betula spp. (birches)Damage: No information available. Species damage unknown. Several Xylotrechusspecies are potential survey targets.Nichole K. Campbell is a pest survey specialist with the USDA, APHIS, Plant Protection and Quarantine program.Milan Zubrik, Forest Research Institute – Slovakia, Bugwood.orgExotic Beetles 35

allows new pest populations to build. Beetle Patrol In 2009, PPQ is conducting exotic beetle trap-ping around the Boston port area as part of the USDA’s national wood borer and bark beetle survey. The Boston port area may be a high-risk Searching for Exotic Beetles Nichole K. Campbell Pe T er Del Tre DICI